Scientists at Russia’s Skoltech have achieved a refined understanding of how plasma treatment can significantly improve the capacitance of supercapacitors.
Their latest findings reveal that a specific mixture of nitrogen and argon plasma can double the areal capacitance of carbon nanowall electrodes.
This could lead to the development of supercapacitors with greater energy storage capabilities and broader applications.
“These are energy storage devices that complement batteries in electric cars, trains, port cranes, and elsewhere,” said the researchers in a press release.
The research focused on the effect of introducing foreign atoms into the carbon material of supercapacitor electrodes through plasma treatment.
Improving the performance of supercapacitors
Supercapacitors are increasingly recognized as vital energy storage devices that work alongside batteries in a variety of applications, from electric vehicles and trains to port cranes and uninterruptible power supplies.
They excel at delivering and harvesting energy rapidly, which makes them ideal for situations requiring quick bursts of power, such as vehicle acceleration and regenerative braking.
Furthermore, supercapacitors boast advantages like wider operating temperature ranges, longer lifespans, and enhanced safety compared to traditional batteries.
“Our team is investigating ways to improve the performance of devices known as supercapacitors by tinkering with the carbon-based material used in their electrodes,” said Assistant Professor Stanislav Evlashin, the principal investigator of the study.
“Basically, there are two ways to increase the amount of energy a supercapacitor stores. Either you enhance the effective surface area of the electrodes by intricate surface design or you introduce foreign atoms into the carbon material of the electrodes.”
Investigating carbon-based electrode performance
The Skoltech team tested the impact of plasma with six different chemical compositions on the capacitance of carbon nanowalls, a material commonly used in supercapacitor electrodes.
Notably, only the plasma composed of a nitrogen and argon mixture resulted in a substantial improvement and doubled the areal capacitance of the material.
“We found that what happens first is that the amorphous carbon remaining after the growth of carbon nanowall structures is cleared away,” explained Evlashin.
“This is followed by the formation of new defects and the incorporation of heteroatoms into the carbon material structure. Amorphous carbon, along with the heteroatoms of nitrogen, contributes to the occurrence of pseudocapacitance.”
Supercapacitors complement batteries in diverse applications
Advances in supercapacitor technology hold significant implications for various sectors. In electric and hybrid vehicles, supercapacitors can improve startup and stopping efficiency, as well as enhance power steering capabilities.
“Working in conjunction with gasoline engines, supercapacitors promise faster charging for vehicle batteries. Electric vehicles in general and trains in particular could benefit from supercapacitors capturing the energy released in braking to boost overall efficiency,” added the press release.
Furthermore, the potential applications extend to the fields of Internet of Things sensors, communication devices, wearable medical devices, and portable electronics.
The ongoing research into electrode modifications is crucial for expanding the toolkit for enhancing supercapacitor performance.
“While this is in no way a record for such carbon-based electrode modifications, the results of the study shed light on the electrochemistry involved,” concluded the press release.